In general, a construction machine such as an excavator includes a side door openably/closably mounted on a side of an engine room mounted on an upper frame so that hydraulic parts inside the side door can be inspected or replaced.
As shown in FIGS. 1, 2(a), 2(b) and 2(c), a door locking device of a construction machine includes:
a side door 1 openably/closably mounted on a side of an engine room;
a locking device case (hereinafter, referred to as “case”) 2 mounted on the side door 1;
a manipulation handle 3 rotatably fixed to the case 2;
a striker 5 mounted on a door frame 4 that openably/closably supports the side door 1;
a locking unit 7 mounted within the case 2 and configured to swingably open/close the side door 1 relative to the door frame 4 by a locker 6 locked to or unlocked from the striker 5 upon manipulating the manipulation handle 3.
As shown in FIGS. 1, 2(a), 2(b) and 2(c), the manipulation handle 3 and the locking unit 7 are assembled integrally so as to be maintained and mounted on the same line of the case 2, and thus the mounting position of the manipulation handle 3 is restricted by the mounting position of the locking unit 7. In this case, the locking unit 7 is preferably mounted at an intermediate point of the entire height of the side door 1 in order to optimize the locking function of the locking device on the side door 1. As a result, the mounting position of the manipulation handle 3 is restricted by the locking unit 7 mounted at the optimized position of the side door 1.
In other words, if the height of the side door 1 is changed depending on the capacity of equipment, the mounting position of the manipulation handle 3 is determined by the mounting position of the locking unit 7, which is required depending on the height of the side door 1. For this reason, the position of a user is deviated from the optimal position of the manipulation handle 3 that can be manipulated to open or close the side door 1 on the ground.
Therefore, the conventional door locking device entails a problem in that the user suffers from an inconvenience in manipulating the locking device to open and unlock the side door 1 or close and lock the side door 1.